Remove some unused variance, with a little remaining breakage in Free.
Backtrack a lot; scalac tricked me.
Avoid illegal variance in bitraverseImpls.
Avoid illegal variance in traverseImpls.
Remove more unused variance.
nuke deprecated classes and methods
Merge pull request #344 from bmjames/scalaz-seven

Minor Readme fixes
Merge pull request #328 from S11001001/topic/hk-ev-variance

Don't break SI-2066 (non-trans)
Fixes #334: remove Float and Double Monoid
remove MetricSpace and BKTree
Merge pull request #340 from larsrh/topic/remove-deprecated

nuke deprecated classes and methods
remove superfluous type parameters in Validation#toValidationNel
Merge pull request #347 from larsrh/topic/remove-metricspace

remove MetricSpace and BKTree
Merge pull request #346 from larsrh/topic/remove-float-monoid

remove Float and Double Monoid
Add InvariantFunctor (from Scalaz 6)
Fix issue where f2 would be evaluated twice in some cases
use variable binding for Some(sa)
Merge pull request #352 from coltfred/scalaz-seven

Fix issue where f2 would be evaluated twice in some cases
Ported ST and Writer examples.
Merge pull request #353 from folone/scalaz-seven

Ported ST and Writer examples.